Currently, a number of consumer electronic devices are adapted to receive speech from a near-end talker (or environment) via microphone ports, transmit this signal to a far-end device, and concurrently output audio signals, including a far-end talker, that are received from a far-end device. While the typical example is a portable telecommunications device (mobile telephone), with the advent of Voice over IP (VoIP), desktop computers, laptop computers and tablet computers may also be used to perform voice communications.
In these full-duplex communication devices, where both parties can communicate to the other simultaneously, the downlink signal that is output from the loudspeaker may be captured or acquired by the microphone. Accordingly, the downlink signal sent back to the far-end device as echo. This echo occurs due to the natural coupling between the microphone and the loudspeaker in electronic devices. The natural coupling may occur, for instance, when the microphone and the loudspeakers are in close proximity, when loud playback levels are being used, and when the microphones in the electronic devices are highly sensitive.
This echo, which can occur concurrently with the desired near-end speech, often renders the user's speech difficult to understand, and even unintelligible is such feedback loops though multiple near-end/far-end playback and acquisition cycles. Therefore, echo degrades the quality of the voice communication.